Translational molecular imaging: Thrombosis imaging with positron emission tomography.

A key focus of cardiovascular medicine is the detection, treatment, and prevention of disease, with a move towards more personalized and patient-centred treatments. To achieve this goal, novel imaging approaches that allow for early and accurate detection of disease and risk stratification are needed. At present, the diagnosis, monitoring, and prognostication of thrombotic cardiovascular diseases are based on imaging techniques that measure changes in structural anatomy and biological function. Molecular imaging is emerging as a new tool for the non-invasive detection of biological processes, such as thrombosis, that can improve identification of these events above and beyond current imaging modalities. At the forefront of these evolving techniques is the use of high-sensitivity radiotracers in conjunction with positron emission tomography imaging that could revolutionise current diagnostic paradigms by improving our understanding of the role and origin of thrombosis in a range of cardiovascular diseases.

Efficient gene editing in induced pluripotent stem cells enabled by an inducible adenine base editor with tunable expression.

The preferred method for disease modeling using induced pluripotent stem cells (iPSCs) is to generate isogenic cell lines by correcting or introducing pathogenic mutations. Base editing enables the precise installation of point mutations at specific genomic locations without the need for deleterious double-strand breaks used in the CRISPR-Cas9 gene editing methods. We created a bulk population of iPSCs that homogeneously express ABE8e adenine base editor enzyme under a doxycycline-inducible expression system at the AAVS1 safe harbor locus. These cells enabled fast, efficient and inducible gene editing at targeted genomic regions, eliminating the need for single-cell cloning and screening to identify those with homozygous mutations. We could achieve multiplex genomic editing by creating homozygous mutations in very high efficiencies at four independent genomic loci simultaneously in AAVS1-iABE8e iPSCs, which is highly challenging with previously described methods. The inducible ABE8e expression system allows editing of the genes of interest within a specific time window, enabling temporal control of gene editing to study the cell or lineage-specific functions of genes and their molecular pathways. In summary, the inducible ABE8e system provides a fast, efficient and versatile gene-editing tool for disease modeling and functional genomic studies.

Establishment and characterization of CSCRi006-A: an induced pluripotent stem cell line generated from a patient with Diamond-Blackfan Anemia (DBA) carrying ribosomal protein S19 (RPS19) mutation.

Diamond-Blackfan anemia (DBA) is a congenital hypoplastic anemia characterized by ineffective erythropoiesis. DBA is majorly caused by mutations in the ribosomal protein (RP) genes (Gadhiya and Wills in Diamond-Blackfan Anemia, https://www.statpearls.com/ ; 2023). A suitable disease model that yields a continuous supply of erythroid cells is required to study disease pathogenesis and drug discovery. Toward this, we reprogrammed dermal fibroblasts from a DBA patient with a heterozygous mutation c.22-23delAG in the RPS19 gene identified through exome sequencing. To generate induced pluripotent stem cells (iPSCs), we induced episomal expression of the reprogramming factors OTC3/4, L-MYC, LIN28, SOX2, and KLF4, and a p53 shRNA2. The DBA-iPSC line CSCRi006-A generated during this study was extensively characterized for its pluripotency and genome stability. The clone retained normal karyotype and showed high expression levels of pluripotency markers, OCT4, NANOG, SOX2, TRA-I-60, TRA-I-81, and SSEA4. It could differentiate into cells originating from all three germ cell layers, as identified by immunostaining for SOX17 (endoderm), Brachyury (mesoderm), and PAX6 (ectoderm). IPSCs provide a renewable source of cells for in vitro disease modeling. CSCRi006-A, a thoroughly characterized iPSC line carrying heterozygous RPS19 c.22-23delAG mutation, is a valuable cell line for the disease modeling of DBA. This iPSC line can be differentiated into different blood cell types to study the mechanisms of disease development and identify potential treatments.

Potential use of bio functionalized nanoparticles to attenuate triple negative breast cancer (MDA-MB-231 cells).

This study showed that bio-functional silver nanoparticles (AgNPs) and zinc oxide nanoparticles (ZnONPs) were synthesized in aqueous extracts of Gymnema sylvestre leaves and tested for toxicity assessment against triple-negative breast cancer cells (TNBC). Biofunctional nanoparticle (NPs) samples were characterized using UV-Vis spectroscopy, FT-IR, XRD, SEM, and TEM. The results showed that the phytofabrication of AgNPs resulted in a dark brown, UV-vis maximum absorbance peak at 413 nm. The AgNPs were crystalline and spherical, with sizes ranging from 20 to 60 nm, as confirmed by the XRD pattern and TEM images. Another phytofabrication of ZnONPs exhibited a white precipitate corresponding to a UV-Vis maximum absorption peak at 377 nm and a fine micro flower morphology with a particle-sized tribution between 100 and 200 nm. In addition, FT-IR spectra showed that bioorganic compounds are associated with NPs that respond to reduced Ag+ ions and AgNPs tabilizers. Invitro cytotoxicity studies revealed the potent anti-cancer effects of phytofabricated AgNPs and ZnONPs on TNBC cells. Furthermore, the AO/EB double staining assay results proved that apoptotic cells are distinguished by greenish-yellow fluorescence of the cell nuclei with IC50 concentrations of 44 ± 0.8 µg/mL for AgNPs and 26.2 ± 0.5 µg/mL for ZnONPs, respectively. Based on our results, we expect that the anticancer function of the biofunctional NPs is due to the apoptotic activation of TNBC cells by increased ROS. Therefore, the presented study demonstrated that biofunctional AgNPs and ZnONPs have excellent prospects for the anti-cancer activity that can be used in pharmaceutical and medical fields.

Chemotherapeutic drugs elicit stemness and metabolic alteration to mediate acquired drug-resistant phenotype in acute myeloid leukemia cell lines.

Chemotherapy resistance leading to disease relapse is a significant barrier in treating acute myeloid leukemia (AML). Metabolic adaptations have been shown to contribute to therapy resistance. However, little is known about whether specific therapies cause specific metabolic changes. We established cytarabine-resistant (AraC-R) and Arsenic trioxide-resistant (ATO-R) AML cell lines, displaying distinct cell surface expression and cytogenetic abnormalities. Transcriptomic analysis revealed a significant difference in the expression profiles of ATO-R and AraC-R cells. Geneset enrichment analysis showed AraC-R cells rely on OXPHOS, while ATO-R cells on glycolysis. ATO-R cells were also enriched for stemness gene signatures, whereas AraC-R cells were not. The mito stress and glycolytic stress tests confirmed these findings. The distinct metabolic adaptation of AraC-R cells increased sensitivity to the OXPHOS inhibitor venetoclax. Cytarabine resistance was circumvented in AraC-R cells by combining Ven and AraC. In vivo, ATO-R cells showed increased repopulating potential, leading to aggressive leukemia compared to the parental and AraC-R. Overall, our study shows that different therapies can cause different metabolic changes and that these metabolic dependencies can be used to target chemotherapy-resistant AML.

Erythroid lineage-specific lentiviral RNAi vectors suitable for molecular functional studies and therapeutic applications.

Numerous genes exert multifaceted roles in hematopoiesis. Therefore, we generated novel lineage-specific RNA interference (RNAi) lentiviral vectors, H23B-Ery-Lin-shRNA and H234B-Ery-Lin-shRNA, to probe the functions of these genes in erythroid cells without affecting other hematopoietic lineages. The lineage specificity of these vectors was confirmed by transducing multiple hematopoietic cells to express a fluorescent protein. Unlike the previously reported erythroid lineage RNAi vector, our vectors were designed for cloning the short hairpin RNAs (shRNAs) for any gene, and they also provide superior knockdown of the target gene expression with a single shRNA integration per cell. High-level lineage-specific downregulation of BCL11A and ZBTB7A, two well-characterized transcriptional repressors of HBG in adult erythroid cells, was achieved with substantial induction of fetal hemoglobin with a single-copy lentiviral vector integration. Transduction of primary healthy donor CD34+ cells with these vectors resulted in >80% reduction in the target protein levels and up to 40% elevation in the γ-chain levels in the differentiated erythroid cells. Xenotransplantation of the human CD34+ cells transduced with H23B-Ery-Lin-shBCL11A LV in immunocompromised mice showed ~ 60% reduction in BCL11A protein expression with ~ 40% elevation of γ-chain levels in the erythroid cells derived from the transduced CD34+ cells. Overall, the novel erythroid lineage-specific lentiviral RNAi vectors described in this study provide a high-level knockdown of target gene expression in the erythroid cells, making them suitable for their use in gene therapy for hemoglobinopathies. Additionally, the design of these vectors also makes them ideal for high-throughput RNAi screening for studying normal and pathological erythropoiesis.

Geraniol enhances peroxiredoxin-1, and prevents isoproterenol-induced oxidative stress and inflammation associated with myocardial infarction in experimental animal models.

This study has explored the fact that geraniol prevents isoproterenol (ISO)-induced oxidative stress and inflammation-mediated myocardial infarction (MI) through enhanced expression of peroxiredoxin-1 (Prdx-1) in experimental animal models. The experimental strategies of MI were stimulated through the subcutaneous direction of ISO (85 mg/kg body weight) for 14 days. ISO-directed models showed elevated heart rate levels and cardiac markers (serum creatine kinase [CK], serum CK-myocardial band, serum C-reactive proteins, and plasma homocysteine); increased cardiac-troponins-T, and troponin-I levels in both serum and myocardium. Moreover, we perceived that a higher level of lipid peroxidation molecules (thiobarbituric acid reactive substances and lipid hydroperoxides) reduced the antioxidant enzyme levels in plasma and heart tissue of ISO-directed rats. However, geraniol treatment prevents ISO-directed enhancement of the heart rate, cardiac and lipid peroxidative genes; reverted the blood pressure, and antioxidant status in ISO-directed rats. Furthermore, gene expression results revealed that geraniol treatment inhibited the mitogen-activated protein kinase (MAPK) proteins, inflammatory responder (tumor necrosis factor-α, interleukin 6, nuclear factor-κB), and cardiac fibrotic proteins (matrix metalloproteinase-2[MMP-2], MMP-9) in ISO directed rats. Prdx-1 is an antioxidant response element, and it can regulate all the antioxidant proteins and it scavenges harmful radicals. Therefore, enhanced Prdx-1 expression is considered to have a pivotal role in preventing cardiac infarction. In this study, an elevated expression of Prdx1 was noticed in geraniol treated with ISO-directed rats. Hence, we concluded that geraniol is considered a potential phytodrug, and it prevents ISO-directed MAPKs, inflammation, and cardiac markers by enhancing the expression of Prdx1.

Regenerative Potential of Stem Cell-derived Extracellular Vesicles in Spinal Cord Injury (SCI).

Spinal cord injury is a devastating condition that is critically challenging and progressive, needing immediate medical attention due to its complex pathophysiology and affecting the social status and economic burden. Stem cell therapy has been the emerging therapeutic trend to treat various diseases for decades. Mesenchymal stem cells pose more advantages over other stem cells in immune-modulation, immune evasiveness, self-renewal, multipotency, etc. Due to various issues in the recent past related to allogenic transplants, ethical concerns in obtaining tissues and adult cells, host immune response, GMP grade production and certification, cell-derived products or cell secretome have proven to be a promising approach and have been implicated in many studies and also in many clinical trials. Utilization of these human MSC-derived exosomes/extracellular vesicles in spinal cord injury has also been demonstrated in many pre-clinical animal models. It is now proven to be therapeutically more efficient and safer than cell therapy. This review focuses on employing human MSC derived EVs for SCI and continues to elucidate the recent advances and emerging EVs trends from other cell types. We discuss biomaterial-based synergistic intervention, mention mimetics and nanovesicles and finally touch upon safety concerns in EV therapy.

Bioengineered gold nanoparticles using Cynodon dactylon extract and its cytotoxicity and antibacterial activities.

In this study, simple and green route approach was applied for the synthesis gold nanoparticles (AuNPs) containing an aqueous extract of Cynodon dactylon L. Pers., (C. dactylon). The synthesized AuNPs were characterized using spectral and microscopic analysis. The changes in the color pattern were observed upon synthesis by UV-vis spectrophotometer with a peak of 530 nm. The FT-IR, XRD, SEM, and TEM were used to analyze the crystal nature and morphology of the green synthesized AuNPs. The C. dactylon-loaded AuNPs in different concentrations (0.625-100 µg/ml) were used to assess cytotoxicity activity against MCF-7 cell line and where the IC50 was found to be 31.34 µg/ml by MTT assay. The C. dactylon-AuNPs were significantly increased reactive oxygen species (ROS) generation, DNA fragmentation, and mitochondrial membrane changes observed by dichlorodihydroflurescenin diacetate (DCFH-DA), 4',6-diamidino-2-phenylindole (DAPI), Rhodamine-123, and acridine orange (AO)/ethidium bromide (EtBr) staining assay. Besides the microbial study revealed that C. dactylon-AuNPs exhibited significant antibacterial activity against clinically isolated pathogenic bacteria such as Enterobacter cloacae, Staphylococus Haemolytics, Staphylococcus petrasii subsp. Pragensis and Bacillus cereus with a zone of inhibition 13, 12, 13 and 12 mm, respectively. It could be concluded that C. dactylon has the ability to be involved in the biosynthesis of AuNPs, and the pharmacological studies proved the promising cytotoxic effect on MCF-7 cell line and pathogenic bacterial species.

Oldest evidence of tuberculosis in Argentina: A multidisciplinary investigation in an adult male skeleton from Saujil, Tinogasta, Catamarca (905-1030 CE).

The Mycobacterium tuberculosis complex (MTC) has affected South American populations since ca. 200 years BCE. In Argentina, possible cases date from ca. 1000-1400 Common Era (CE). This paper describes the oldest (905-1030 CE) confirmed case of tuberculosis (TB) in a young adult male from Lomitas de Saujil (Tinogasta, Catamarca, Argentina). Osteolytic lesions on the bodies of the lower spine were macroscopically and radiographically identified. Bilateral new bone formation was seen on the visceral vertebral third of several ribs and in long bones, compatible with hypertrophic osteoarthropathy. Representative rib and hand bones gave profiles for MTC-specific C27-C32 mycocerosic acid lipid biomarkers; these were strongest in one heavily-lesioned lower rib, which also had MTC-diagnostic C76-C89 mycolic acids and positive amplification of MTC-typical IS6110 aDNA fragments. During the first millennium CE, the intense social interaction, the spatial circumscription of villages among the pre-Hispanic societies in the mesothermal valleys of Catamarca and the fluid contacts with the Eastern lowlands, valleys and puna, were factors likely to favor disease transmission. It is proposed that TB arrived from northern Chile and dispersed towards the northeast into the Yocavil valley, where several cases of TB infection were macroscopically identified for a later chronology.

Naringin, a Natural Flavonoid, Modulates UVB Radiation-Induced DNA Damage and Photoaging by Modulating NER Repair and MMPS Expression in Mouse Embryonic Fibroblast Cells.

We have proven that naringin, a phytonutrient, diminishes oxidative damage and inflammatory responses by modulating PPAR-γ expressions in ultraviolet-B radiation (UVB)-induced NIH-3T3 cells. However, the role of naringin against DNA damage, photoaging, and apoptosis in NIH-3T3 cells has yet to be studied, necessitating investigation. We show that Naringin pretreatment significantly reduces UVB-induced alkaline DNA damage and potentially modulates NER gene (XPC, TFIIH, XPE, ERCC1, and GAPDH) expression, thereby augmenting DNA repair. We determined experimentally that naringin pretreatment prevents UVB-induced nuclear fragmentation in NIH-3T3 cells, as well as altering UVB-induced apoptotic marker (Bax, BCl-2, Caspase-9, and Caspase-3) expression in them. In addition, naringin pretreatment inhibits UVB-stimulated matrix metalloproteinase (MMP-2, MMP-9 and MMP-13) expression in these 3T3 cells. Therefore, we report that naringin can effectively avert UVB-mediated DNA damage, photoaging, and apoptosis in NIH-3T3 cells.

p-Coumaric acid attenuates alcohol exposed hepatic injury through MAPKs, apoptosis and Nrf2 signaling in experimental models.

Overconsumption of alcohol could lead to severe liver injury that connects with oxidative stress, apoptosis, and inflammatory response. Previously, we proved that p-coumaric acid prevents ethanol induced reproductive toxicity; however, p-coumaric acid (PCA) on ethanol mediated hepatotoxicity has not been examined yet. In our work, we sought to study the potential of PCA in contradiction of ethanol induced hepatoxicity which linking with MAPKs, apoptosis, oxidative stress, and Nrf2 signaling. Foremost, we found that PCA could protect ethanol induced both L-02 and HepG2 hepatic cells by inhibiting cytotoxicity, ROS production, mitochondrial depolarization, and nuclear fragmentation. Also, in vivo experiments showed that the ethanol increasing the lipid markers (TBARS, CD) and depletes the antioxidants thereby increased phosphorylation of JNK, ERK, and p38 in rat liver tissues. Interestingly, PCA treatments inhibit ethanol exposed lipid markers and depletion of antioxidants, which directs the inhibition of MAPKs activation in rat liver tissues. We also noticed that the PCA protected ethanol induced apoptosis and liver markers by inhibiting the expression of Bax, caspases; AST, ALT, ALS, and LDH in liver tissue. Overall, the ameliorative consequence of PCA on ethanol induced oxidative stress and apoptosis was achieved by suppressing the expression of CYP2E1 and overexpressing Nrf2 and its target protein HO-1 in rat liver tissue. As a result, PCA was marked to be an effective antioxidant with notable hepatoprotection by inhibiting MAPKs and apoptosis signaling via enhancing Nrf2 signaling.

Antidiabetic Activity of Gold Nanoparticles Synthesized Using Wedelolactone in RIN-5F Cell Line.

We synthesized the gold nanoparticles (AuNPs) using wedelolactone (WDL) and characterized them using UV-visible spectroscopy, fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopic (SEM), transmission electron microscopic (TEM), energy dispersive X-ray diffraction, and atomic force microscopic (AFM) studies. The electronic spectrum exhibited an absorption peak at 535 nm. The FT-IR results proved that WDL was stabilized on the surface of AuNPs by acting as a capping or reducing agent. The crystalline structure was affirmed by XRD pattern and the spherical shape of WDL-AuNPs was evidenced by SEM, TEM, and AFM. The synthesized WDL-AuNPS were evaluated for anti-diabetic activity in pancreatic RIN-5F cell lines. In vitro results showed that WDL-AuNPs did not only improve the insulin secretion affected by di-(2-ethylhexyl) phthalate (DEHP), but also the cell viability in RIN5F cells. WDL-AuNPs treatment modulates the pro-apoptotic proteins and anti-apoptotic proteins expression to prevent the cells undergoing apoptosis in DEHP-exposed RIN-5F cells. The exposure of DEHP causes an increase in ROS production and lipid peroxidation levels. The free radical scavenging and antioxidant properties of WDL-AuNPs increase the deleterious effect caused by DEHP. On the other side, WDL-AuNPs increase mRNA expressions of insulin-signaling proteins in RIN-5F cells. This study concludes that WDL-AuNPs can be successfully used to regulate the expression of Bcl-2 family proteins, reduce lipid peroxidation, and to improve the secretion of antioxidants and insulin through the GLUT2 pathway in RIN-5F cell lines.

Adherence to the recommended timing of focused antenatal care in the Accra Metropolitan Area, Ghana.

INTRODUCTION: The proportion of antenatal attendants in Ghana who had at least four antenatal visits increased from 78% in 2008 to 87% in 2014. However, it is not known whether these visits followed the recommended timing of focused antenatal clinic attendance in Ghana. We sought to assess the adherence to the clinic schedule and its determinants in the Accra Metropolis. METHODS: A cross-sectional study was conducted. Face-to-face interviews were conducted with postpartum women. Multiple logistic regression was used in the analysis of determinants of adherence to the recommended timing of clinic attendance. A p-value of <0.05 was considered statistically significant. RESULTS: Among 446 focused antenatal care clinic attendants, 378 (84.8%) had four or more visits. Among these, 101 (26.7%) adhered to the recommended clinic schedule. Women who adhered were more likely to have had education up to Junior High School [AOR=3.31, 95%CI (1.03-10.61)] or Senior High School [AOR=4.47, 95%CI (1.14-17.51)], or have history of abortion [(AOR=3.36, 95%CI (1.69-7.96)]. For every week increase in gestational age at booking at the antenatal clinic, respondents were 34% less likely to complete all four antenatal visits at the recommended times. [(AOR=0.66, 95% (0.60-0.73)]. CONCLUSION: Majority of women receiving focused antenatal care in the Accra Metropolis have four or more visits but only about a quarter of them adhered to the recommended clinic schedule. Having high school education, history of abortion and early initiation of antenatal care were predictors of adherence to clinic schedule. Women should be educated on early initiation of antenatal care to enhance adherence.

Biopolymers augment viral vectors based gene delivery.

The success of viral vectors mediated gene therapy is still hampered by immunogenicity and insufficient transgene expression. Alternatively, non-viral vectors mediated gene delivery has the advantage of low immunogenicity despite showing low transgene expression. By carefully considering the advantages of each approach, hybrid vectors are currently being developed by modifying the viral vectors using non-viral biopolymers. This review provides an overview of the hybrid vectors currently being developed.

Phloretin loaded chitosan nanoparticles enhance the antioxidants and apoptotic mechanisms in DMBA induced experimental carcinogenesis.

The main aim of this study was to investigate the effects of phloretin loaded chitosan nanoparticles (PhCsNPs) on 7,12-dimethylbenz[a]anthracene (DMBA) induced experimental cancer in hamsters. Oral squamous cell carcinoma (OSCC) was induced in male golden Syrian hamsters by painting with 0.5% DMBA three times a week for 14 weeks. Varying concentration of PhCsNPs (5, 10, and 20 mg/kg b.wt.) was orally administered on alternative days to evaluate the optimum dose. The experiment design was terminated at the end of the 14th week. The development of OSCC was confirmed by histopathological and biochemical analysis (lipid peroxidation, antioxidant profile, and detoxification enzymes) in plasma, erythrocyte, buccal, and liver tissues. Significant increases in oxidation and lipid peroxidation were noticed in DMBA-painted hamsters. Oral administration of PhCsNPs in various doses on alternate days reversed the deleterious effects induced by DMBA. In addition, immunoblot analyses of PhCsNPs treatment enhanced the release of Bcl-2 associated X protein (Bax), cytochrome c, caspase-3, 9 and suppressed the B-cell lymphoma 2 (Bcl-2) expression, which the use of PhCsNPs for mitochondrial-mediated apoptosis. These findings suggest biofabricated PhCsNPs may act as a potent antioxidant and anti-carcinogenic in DMBA induced oral cancer in experimental animals.

Phloretin loaded chitosan nanoparticles augments the pH-dependent mitochondrial-mediated intrinsic apoptosis in human oral cancer cells.

The aim of the present investigation is to explore the innovative platform for the synthesis of plant-based nanoparticles, which contain biocompatible and biodegradable carrier of chitosan loaded with phloretin hydrophobic phytochemical applied as a stable anticancer agent. Treatment of cancer uses chemotherapeutic drugs as the cells are resistant to other drugs. However, the usage of therapeutic drug is limited by its poor solubility and low bioavailability. To overcome this problem, we fabricated the phloretin loaded chitosan nanoparticles (PhCsNPs) and physicochemical properties of PhCsNPs were characterized by FTIR, XRD, DLS, SEM and TEM. The findings indicated that the synthesized PhCsNPs were spherical and homogeneous in shape with the size distribution of 80-100 nm and exhibited stability in ultimate drug releasing profile. Further, we substantiated the anticancer efficiency of PhCsNPs through bio-assessment, such as cytotoxicity measurement, intracellular ROS, mitochondrial dysfunction, lipid peroxidation measurement, antioxidants status, apoptotic associated gene expression profile and cell cycle analysis in human oral cancer cell lines. The findings suggested that PhCsNPs augmented the mitochondrial-mediated apoptotic mechanism through the stimulation of oxidative stress, depletion of cellular antioxidants and cell cycle arrest. Our data suggested that PhCsNPs could be used as an efficient therapeutic agent for the treatment of oral cancer.

Pharmacological Aspects and Potential Use of Phloretin: A Systemic Review.

Over the past two decades, many researchers have concluded that a diet rich in polyphenolic compounds plays an important therapeutic role in reducing the risk of cancer, cardiovascular disease, inflammation, diabetes, and other degenerative diseases. Polyphenolic compounds have been reported to be involved in neutralization of reactive oxygen species and charged radicals, and have anticarcinogenic effects, hepatoprotective effects, low-glycaemic response, and other benefits. The benefits of fruits and vegetables may be partly attributable to polyphenolic compounds, which have antioxidant and free radical scavenging properties. Fruits such as apples contain a variety of phytochemicals, including (+)-catechin and (-)-epicatechin, phlorizin, phloretin quercetin, cyanidin-3-Ogalactoside, chlorogenic acid, and p-coumaric acid, all of which are strong antioxidants. Phloretin, a natural phenolic compound, is a dihydrochalcone, which is present in the apple. It exhibits a wide variety of activities such as antioxidative, anti-inflammatory, anti-microbial, anti-allergic, anticarcinogenic, anti-thrombotic, and hepatoprotective, besides being involved in the activation of apoptotic associated gene expression and signal transduction in molecular pathways. Despite a multitude of clinical studies, new efforts are needed in clinical research to determine the complete therapeutic potential of phloretin.

A generalised enzyme kinetic model for predicting the behaviour of complex biochemical systems.

Quasi steady-state enzyme kinetic models are increasingly used in systems modelling. The Michaelis Menten model is popular due to its reduced parameter dimensionality, but its low-enzyme and irreversibility assumption may not always be valid in the in vivo context. Whilst the total quasi-steady state assumption (tQSSA) model eliminates the reactant stationary assumptions, its mathematical complexity is increased. Here, we propose the differential quasi-steady state approximation (dQSSA) kinetic model, which expresses the differential equations as a linear algebraic equation. It eliminates the reactant stationary assumptions of the Michaelis Menten model without increasing model dimensionality. The dQSSA was found to be easily adaptable for reversible enzyme kinetic systems with complex topologies and to predict behaviour consistent with mass action kinetics in silico. Additionally, the dQSSA was able to predict coenzyme inhibition in the reversible lactate dehydrogenase enzyme, which the Michaelis Menten model failed to do. Whilst the dQSSA does not account for the physical and thermodynamic interactions of all intermediate enzyme-substrate complex states, it is proposed to be suitable for modelling complex enzyme mediated biochemical systems. This is due to its simpler application, reduced parameter dimensionality and improved accuracy.